Road to Recovery

One of the snakes being released receives a fluorescent coating to enable scientists to temporarily track it. Photo by Sharon Dewar.

Restoring Smooth Green Snakes to the Region

Coated in fluorescent powder, three smooth green snakes made their way into the Lake County Forest Preserve landscape. By using black lights to trace the trail left behind, researchers with Lincoln Park Zoo and the forest preserve district hope to establish a path that will end with these native snakes being restored to the region.

Small, vibrant insect eaters, smooth green snakes naturally make their homes in prairies and marshes—areas desirable for human development. The reptiles’ numbers declined in Lake County as houses and farms sprung up. Even after forest preserve biologists restored native habitat, the snakes didn’t recolonize the area on their own. “The landscape seemed to meet their needs, but the snakes just weren’t returning,” says Conservation Biologist Joanne Earnhardt, Ph.D.

Another approach was needed. So the Forest Preserve began a conservation partnership with Lincoln Park Zoo. By establishing a zoo-based breeding program, the collaborators aimed to build a healthy population for eventual release into the wild.

A large clutch of eggs rescued from land slated for development provided a fortuitous head start. Lincoln Park Zoo welcomed 83 hatchlings last summer. These were unprecedented arrivals, as no other accredited zoo had yet bred the species. “There isn’t much published information out there,” says Curator Diane Mulkerin. “We’re breaking new ground in caring for them.”

Lincoln Park Zoo’s expert animal care staff worked with researchers to discover the best methods for rearing the young snakes. While half were raised at the zoo, the others matured in protected shelters in the Lake County Forest Preserve. These accommodations provided natural food and habitat while offering protection from predators.

After a year of growth, the conservation partners decided the time was right to release the first set of snakes into natural homes in the wild. The three snakes coated in powder made their way into the camouflaging grasslands. Three others were placed in the soft-release enclosures to study whether acclimation eases a future release.

While the powder will wear off, future snakes will be equipped with tiny radio transmitters enabling the researchers to follow them as they establish themselves in their new homes. The nondisruptive devices are attached to the snakes’ scales and will be cast off when the snakes undergo their next shed.

“We need to follow along to see where they like to live and how they’re establishing themselves in their new homes,” says Reintroduction Biologist Allison Sacerdote, Ph.D. “It’s that kind of data that will help us restore them to the wild.”

Restoring the Smooth Green Snake Slideshow
Lincoln Park Zoo scientists are working with the Lake County Forest Preserve District to restore wild populations of the smooth green snake. Follow researchers into the field in August 2010 as they introduce new hatchlings to safe housing.